<!--
 * @Author: fcli
 * @Date: 2023-09-04 10:34:58
 * @LastEditors: fcli
 * @LastEditTime: 2023-09-07 09:05:17
 * @FilePath: /vue-vercode/src/plugin/index.vue
 * @Description: 验证码
-->


<template>
    <canvas class="canvas" ref="cav" @click="Refresh"></canvas>
</template>
<script lang="ts" setup>
import { ref, onMounted } from 'vue';
const show_num = ref<any>([])
const cav = ref<any>(null)
onMounted(() => {
    draw();
});
const draw = () => {
    var Canvas_DOM = cav.value;
    var cav_width = Canvas_DOM.clientWidth;
    var cav_height = Canvas_DOM.clientHeight;
    var context = Canvas_DOM.getContext('2d');
    Canvas_DOM.width = cav_width;
    Canvas_DOM.height = cav_height;
    var sCode =
        // "A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0";
        'a,b,c,e,f,g,h,j,k,l,m,n,p,q,r,s,t,w,x,y,z,1,2,3,4,5,6,7,8,9,0';
    var aCode = sCode.split(',');
    var aLength = aCode.length; //获取到数组的长度

    for (var i = 0; i <= 3; i++) {
        var j = Math.floor(Math.random() * aLength); //获取到随机的索引值
        var deg = (Math.random() * 30 * Math.PI) / 180; //产生0~30之间的随机弧度
        var txt = aCode[j]; //得到随机的一个内容
        show_num.value[i] = txt.toLowerCase();
        var x = 50 + i * 20; //文字在canvas上的x坐标
        var y = 20 + Math.random() * 8; //文字在canvas上的y坐标
        context.font = 'bold 23px 微软雅黑';

        context.translate(x, y);
        context.rotate(deg);

        context.fillStyle = _randomColor();
        context.fillText(txt, 0, 0);

        context.rotate(-deg);
        context.translate(-x, -y);
    }
    for (var i = 0; i <= 5; i++) {
        //验证码上显示随机线条
        context.strokeStyle = _randomColor();
        context.beginPath();
        context.moveTo(Math.random() * Canvas_DOM.width, Math.random() * Canvas_DOM.height);
        context.lineTo(Math.random() * Canvas_DOM.width, Math.random() * Canvas_DOM.height);
        context.stroke();
    }
    for (var i = 0; i <= 30; i++) {
        //验证码上显示随机小点
        context.strokeStyle = _randomColor();
        context.beginPath();
        var x = Math.random() * Canvas_DOM.width;
        var y = Math.random() * Canvas_DOM.height;
        context.moveTo(x, y);
        context.lineTo(x + 1, y + 1);
        context.stroke();
    }
}
const _randomColor = () => {
    //得到随机的颜色值
    var r = Math.floor(Math.random() * 256);
    var g = Math.floor(Math.random() * 256);
    var b = Math.floor(Math.random() * 256);
    return 'rgb(' + r + ',' + g + ',' + b + ')';
}
const Refresh = () => {
    draw();
}
</script>
<style  scoped>
.canvas {
    width: 200px;
    height: 40px;
    display: inline-block;
    margin-left: 12px;
    cursor: pointer;
}
</style>
